Table of Contents
Advertisement
FM reception characteristics
In general, FM has much better tonal quality than AM.
However, FM and FM stereo reception encounter several
characteristic problems not encountered with AM. FM is
more difficult to receive than AM in a moving vehicle. The
following are explanatory notes on what to expect from FM
reception and on how to get satisfactory performance.
1 .
FM RECEPTION DIFFERS FROM AM
A characteristic of transmitted signals is that lower
frequencies travel further. FM frequencies are much
higher than AM's (similar to a ray of light): they won't
bend but they will reflect. Often, they will be interrupted
by tall buildings, mountains, etc., taking direct and
indirect paths to your vehicle's antenna. The distance at
which FM stations can be received satisfactorily is
usually not nearly as far as that which AM stations can
be received.
AM Radio Waves
Ionosphere
2 .
FADING OUT
In weak signal or "fringe" reception areas, FM stations
may fade out completely, or fade in and out. When
driving in weak signal areas, such as near hills, through
valleys or tunnels, among tall buildings, etc., you may
encounter unusual noise interference. THIS IS NOT A
TUNER PROBLEM. In this case, you can only wait until
you are in a better reception area, tune to a stronger
station, or reduce the treble level.
How to operate the tuner
FM Radio Waves
Ionosphere
35
Advertisement
Table of Contents
